Pressurized Fermentation for Room Temp "Lager"

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SouthPhillyBr3w3r

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I just recently listened to an episode of the Beer Smith podcast where Chris White and John Blichmann discussed fermenting under pressure. They did an experiment fermenting four identical beers (Munich Helles) under different conditions:

The first beer was fermented at lager temps at ambient pressure. The second was fermented at 68'F at ambient pressure. The third was fermented at 68'F at 15 psi, and the last was fermented at 68'F at 30 psi.

They used quantitative analysis (gas chromatography) to determine the amount of esters in each beer. The elevated pressure beers had less esters than even the lager fermented beer. While they claim that the lager fermented beer was identifiable by its higher level of sulfur compounds, I feel like this is a perfectly viable way to make lager styles without a temp control chamber.

Has anyone tried fermenting "Lagers" at room temp under pressure? Seems like a good way to make them quickly without refrigeration.
 
I am finishing a batch at this very moment. I was reading a different pressure ferm post and read about that very yeast that Chris was talking about. It's WLP925 high pressure lager yeast and it had been moved from their vault to their primary catalog so I wonder if it's gaining popularity? I had a spare corny keg available and some extra parts to build the spunding valve (just needed the adjustable PRV) so I decided to give it a try.

Here are my notes so far:

I made a very simple Helles recipe with pilsner,munich malts and hallertauer hops. I figured the simpler the better that way I could tell if something tasted weird.

I didn't exactly hit my target OG 1.048 but was close enough (1.046). I pitched two packs of the wlp925 because I didn't want to mess with a starter. I filled the keg to about 90%, 4.5g?( I splashed filled and shook for my oxygenation step) I did not use ferm cap or start with a blowoff tube like others do. I'm am testing with minimal fussing around because Im looking for a process which is "set it and forget it".

I had previously dialed in the spunding valve with my air compressor because the markings are not very exact. I then set the corny inside a cooler in my garage and wrapped some egg foam around it. I set a thermometer next to the keg and let it rip. Temp in the garage was fairly constant 68F (i live in San Diego) but the Thermo climbed to about 72F after three days or so then back to 68F. I didn't check for seven days (which was Frustrating because I was excited to try it and you can't watch the activity in the keg or watch bubbles in an airlock).

7 day gravity test was 1.011(target was 1.010) I pulled the sample from a picnic tap run from the liquid ball lock. First cup was pretty cloudy but cleared up after that. The beer was foamy and a little carbonated too! I made sure to de-gas the sample before checking the gravity again. My first impressions we're that the beer was not bad if maybe a little boring. I did not detect any obvious off flavors but I don't have the most discerning palette. My wife DOES tho and she would be able to tell if something was wrong. She said it tasted like flat Corona. I'm perfectly fine with that! 9 day reading was today and still 1.011 so tomorrow I'll be transferring to serving keg and cold crashing in the keezer. If I burst carbonate I could be drinking pints by Sunday which is 2 weeks grain to glass. I'll be drinking and passing out some samples to friends and family. If the results come back positive then this will be my new process going forward because it was dead easy. I'm also thinking about changing the liquid dip tube for a floating dip tube and serving right from the fermenting keg! I haven't seen many posts about doing that part so I'll have to experiment with it myself.

I probably will use a starter to save$ on yeast and double purpose my keezer in the summer to keep the temps reasonable but other than that I think this could be the way to go. Hope this helps and I will update when I get some feedback.
 

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Has anyone tried fermenting "Lagers" at room temp under pressure? Seems like a good way to make them quickly without refrigeration.

First thing to do would be to try making one at room temp without pressure, with something like 34/70 per the warm-fermented lager thread and see how you get on with that. It does help if you can keep the temp steady though, you'll get a cleaner beer at say steady 65F than at a variable 60F.
 
NorthernBrewer, Thanks for the suggestion. ArraSmithF, I really appreciate the detail in your post! I would be greatly interested to hear how the beer is once it is cleared, carbed, and cold!
 
NorthernBrewer, Thanks for the suggestion. ArraSmithF, I really appreciate the detail in your post! I would be greatly interested to hear how the beer is once it is cleared, carbed, and cold!
Initial results are in and positive! After my last post I transferred to serving keg, crashed to 35F and used the burst carbonation method learned from the Brulosophy website, which is 40 PSI for 24 hours, then vented the pressure and set to my serving pressure (15) and let sit overnight. Yes, I transferred before crashing but I needed my fermenting keg ready for another batch so there was a little bit of sediment in the first pour but not much. This will hopefully cease to be a problem as I am going to try the floating dip tube in my next batch. Anyway, my wife and I sampled the beer while bottling some samples for friends. She was very impressed and I was pleasantly surprised. tonight at dinner we had a few more glasses and I was even more encouraged. She gave me a 4 out of 5. I was at a solid 3, but that was my biased opinion because I know that my brew targets were missed and I thought it would have been better if I hit them, but who knows. My wife's final thought was that it tasted like summer, so as far as I'm concerned, I nailed it. I'm waiting on results from my friends who I have instructed to provide honest reviews or they get no more free beer. I even sent my samples out with scorecards. To sum up, the fermenting in the keg was super easy and the wlp925 is a good yeast that I will definitely use again, and very soon. With a few tweaks and some refinement of the process, This beer could easily be a regular beer on tap for me. i will also be ordering this floating dip tube from here:

https://www.morebeer.com/products/r...t-60-cm-silicone-dip-tube-fermentasaurus.html

so I can experiment with serving from the fermenting keg.

either way, I like the idea of pulling beer from the top so even if I don't serve straight from fermenter, I can be less concerned with transferring sediment.
 
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I'm on day 7 now will a helles export, fermented using the Fermentasaurus.

The first 3 days the wort was in an regular airlock bucket because my shipment was delayed.

Yeast - saflager s-23 at 21C ambient.

Fermentation is no longer building pressure. 3 days in the tank i had the PRV set to 20psi. But earlier today i purged all the sulphur smells and added fresh CO2 from my tank to 14psi and holding, PRV is closed.

Will siphon to keg monday or tuesday and cool crash, fine with gelatin.
 
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